Low-valent zirconocene-mediated cyclization of γ,δ-unsaturated oximes
摘要:
gamma,delta-Unsaturated O-methyl oximes were cyclized to dihydropyrrole by the treatment of (1-butene)ZrCp2 3 prepared by Negishi's procedure (reaction with Cp2ZrCl2 and two equivalents of n-BuLi). In this cyclization, the geometry of oximes was affected and syn-oximes were cyclized efficiently. However, it was found that the anti-oxime is not suitable for the cyclization. (C) 2010 Elsevier Ltd. All rights reserved.
of an O-(4-methoxybenzyl) oxime ether bearing an olefin substituent and 1-chloroanthraquinone (1-Cl-AQN) catalyst in 2-butanone under visible-light irradiation affords pyrroline via an iminyl radical intramolecular hydroimination. Mechanistic studies indicate that iminyl radical generation mainly proceeds by hydrogen abstraction of the photocatalyst from the benzyl position of the oxime. Moreover,